Reversing mechanism for drilling machines



July 3, 1928. 1,675,850

R. M. GALLOWAY ET AL REVERSING MECHANISM FOR, DRILLING MACHINES Filed Aug. 1, 1923 2 Sheets-Sheet 1 lilvamns 25 Faber/6M Galawcu 7? 7740 Nd 6152 7307? Jlaiy 3, 1928.

R. M. GALLQWAY ET AL,

REVERSING MECHANISM FOR DRILLING MACHINES Fil ed Aug. 1, 1923 2 Sheets-Sheet 2 M| wH H H wi l: m

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Patente July 3, 1928.

UNITED STATES PATENT OFFICE.

ROBERT MNGALLOWAY AND RAYMOND E. STERLING, OF RICHMOND, INDIANA, AS-

SIGNORS TO THE NATIONAL AUTOMATIC TOOL COMPANY,

A COREORATION OF INDIANA.

OF RICHMOND, INDIANA,

REVERSING MECHANISM FOR DRILLING MACHINES.

Application filed August 1, 1923.

This invention relates to improvements in drilling machines and its purposeis to provide improved means for automatically reversing the driving mechanism of the drill spindles. The principal object of the invention is to provide automatic reversing mechanism which may be adjusted to operate at different positions of the drill head and its spindles so that the machine may one embodiment is illustrated. In the draw.-

ings Fig. 1 shows a partial side elevation of a drilling machine having the improvement of the present invention applied thereto; Fig. 2 shows a vertical section through the gearing mechanism by'which the spindle driving shaft is operated, showing a partial side elevation of the mechanism for reversing the direction of rotation of the shaft; Fig. 3 is a detailed section taken on the line 33 of Fig. 1, and Fig. 4 shows a top plan view of the adjustable dog by which the reversing mechanismis operated.

The invention is shown applied to a drilling machine comprising a verticalstand ard 10 carrying at its upper end the transverse casing 11 which has mounted in suitable bearings therein a horizontal shaft 12. The shaft '12 projects from one endof the case and a drive pulley 13 is secured thereon between the casing and the bracket 14:, a pulley being driven'by a belt in the usual manner. In the portion of the casing 11 which projects from the other side of the standard, there is mounted the gearing mechanism by which the shaft 12 operates the vertical spindle driving shaft 15. This mechanism comprises a bevel gear 16 secured to the end of the shaft 12 and arranged to mesh with two other bevel gears 17 and 18 which are rotatably mounted in the hubs 20 located in the upper and lower Serial No. 655,009.

walls of the gear casing. The gears 17 and 18 are provided with bushings 21 which rotatably engage the vertical shaft 15. The gears 17 and 18 are further provided on their opposing faces with clutch teeth 22 which are adapted to be engaged by the similar teeth of a clutch member 23 which is splined on the shaft 15 between the gears and provided with an annular groove 23 adapted to be engaged by the lugs 24 extending inwardly from the divergent arms 25 of a shifting lever 26. This lever is pivoted at 27 within the casing and projects outwardly through an opening in the casing to be engaged by the reversing mechanism.

The shaft 15 is capable of sliding vertically within the bushings of the gears 17 and 18 and within the clutch member 23 which is splined thereon so that in any position of this shaft with respect to the horizontal shaft 12, it is adapted to drive the drill spindles 28 which are mounted in the drill head 30 and adapted to be operated from the shaft 15 by means of gears and pinions in the usual manner. The drill head 30 is mounted to slide vertically on the guideway 31 which is formed on the standard 10 and the vertical movement of the head is effected by suitable driving mechanism comprising a pinion engaging the rack 32 which is secured to the face of the standard 10. When the head is being lowered and the drills or taps carried by the drill spindles are in engagement with the work being operated upon, the shaft 15 will be operatedin the normal clockwise direction and when the holes have been completely drilled or tapped, the lever 26 is shifted to bring the clutch member-23 intoengagement with the other bevel gear, whereupon the direction of rotation of't'he shaft 15 and of the drill spindles is'reversed.

This operation of the lever 26 to effect the reversal of the drill spindles isetfected automatically by mechanism which is actuated by the movement of the head 30. A bracket 35 extends outwardly from the casing 11 and is provided with a vertical bore 36 en gaged by a plunger 37 which is normally moved in a downward direction by the COll spring 38 which is mounted in the bore and arranged to co-act at its upper end with the adjustable threaded plug 39. The plunger 37 engaging the lever 26 normally tends to move the clutch member 23 in an upward direction into engagement with the bevel gear 17 so that the shaft 15 is normally driven in the reverse direction, corresponding to an anti-clockwise rotation of the drill spindles. A plate 40 is adjnstably secured to a lug 41 on the side of the lever 26 by means of screws 42 and this plate is adapted to be engaged by the upper end of the latch plate 43 which is secured to the inner side of an operating handle 44 by means of screws 45. The plate 43 is adjustable on the handle 44 by means of the screw 46 engaging the lug 47 formed on the handle. The lever 44 is pivoted at 48 on the bracket 35 and is provided with a transverse arm 49 extending laterally from the pivot 48 and provided at its end with a collar 50 loosely engaged by the vertical trip rod 51. A coil spring 52 is mounted on the rod 51 between the collar 50 and a fixed collar 53 which is formed on the casing 11 so that the spring 52 normally tends to force the operating handle 44 inwardly toward the casing 11 about the pivot 48. When the shift lever 26 is moved upwardly to bring the clutch member 23 into engagement with the clutch teeth of the lower bevel gear 18, it is adapted to be held in that position by a latch plate 43 extending beneath the end of the plate 40 and, as previously indicated, the handle 44 is nor mally held in a position to engage the looking plate 40 by the action of the coil spring 52.

When the drill head has reached the-predetermined lower limit of its stroke; the operating handle 44 is moved outwardly to release the plate 43 from the plate 40. and thereby permit the reversal of the clutch mechanism, due to the action of a trip dog 55 adjustably secured to' the upper part of the tri rod 51 by means of a set screw 56. The trip dog 55 is provided with a plurality of vertical apertures each of which is slidably en aged by a stem 57. These stems are adjustably secured in their respective apertures by the set screws 58 and their positions may be regulated to vary the relative positions of their lower extremities and the dog 55 may be turned and adjusted vertically on the trip rod 51 to bring any one of the stems 57 into position above the arm 49 .of the operating handle 44.

The dog 55 is actuated to bring one of the stems 57 into engagement with the extension 49 of the handle 44 by the vertical movement of the trip rod 51 which has its lower end connected to the drill head 30. This connection is formed by means of a socket member 60 which is attached to the drill head and adapted to receive the lower end of the rod 51. The rod has a pin 61 projecting from the lower end thereof to engage an annular groove 62 within the socket member so that the rod is capable of turning in the member 60 but cannot move vertically with respect thereto. It will be apparent that when the rod 51 moves downwardly with the drill head, one of the stems 57 will engage the extension 49 of the operating handle and that this enga ement may be caused to occur at any pre etermined time in the operation of the drilling machine, due to the various adjustments which may be made in the positions of the stems in the dog 55 and the position of the dog on the vertical rod 51.

The rod 51 is turned to regulate the positions of the stems 57 with respect to the part 49 of the operating handle by means of a crank arm 64 which is connected to the lower end of the rod, and adapted to be operated by a connecting rod 65. The other end of the-connecting rod is pivotally connected to a crank arm 66 which is secured to the upper end of a vertical shaft 67 mounted in bearings carried by the brakets 68 and 69 secured to the drill head. The vertical movement of the shaft 67 is prevented by a collar 70 which is secured thereto above the lower bracket 69 and the rotation of this shaft is effected by a handle 71 secured to the lower end thereof. When the handle 71 is rotated a corresponding rotation of the trip rod 51 takes place and the trip rod is held in the desired adjusted position by means of a plate 73 which is secured to the socket member 60 and which is provided on its upper side with a plurality of depressions 74 adapted to be engaged by a pin 75 which projects downwardly from the pivotal connection of the crank arm 64 and the connecting rod 65, this pin being actuated by a spring so that it will be released from any one of the depressions 74 and slide over the face of the plate 73when suflicient pressure is brought'to bear on the handle 71. By rotating the handle 71, the rod 51 may be readily secured in a position wherein any one of the stems 57 will engage the ex tension 49 of the operating handle or wherein none of these stems will engage part 49, so that the mechanism may be adjusted to cause the reversal of the spindle driving mechanism at any predetermined depth of the drill head or to permit the continued operation of the spindle driving mechanism without reversal.

When the spindle driving mechanism is reversed, the spindles continue to rotate in the reversed directions until the head 30 is again moved upwardly to a sufficient degree to cause the arm 77 of the lower trip dog 77 to engage the shift lever 26 and raising it to the position illustrated in Fig. 1. When the lever 26 is elevated against the pressure of the coil spring 38 which actuates the plunger 37, the plate 40 rides upwardly on the face of the latch plate 43 until the net/trace plate 43 snaps inwardly beneath the end thereof due to the action of the coil spring 52 on the extension 49 of the operating handle. The shift lever 26 is then located in position to effect the rotation of the drill spindles in the forward direction and this action continues until the drill head is again lowered sufficiently to bring one of the stems 57 into engagement with the part 49 of the operating handle. The lower trip dog 77 is secured on the trip rod 51 by means of a set screw 78, and its position may be varied to cause the upward movement of the shift lever 26 when the head 30 reaches any predetermined point in its upward movement.

Although one form of the invention has been shown and described for the purpose of illustration, it will be understood that it may be constructed in various other embodiments without departing from the scope of the appended claims.

We claim:

1. A drilling and tapping machine combining a translatable tool-head; a spindle driving shaft carried by said tool-head, a forward and a reverse drive for said shaft; a clutch embodied in each of said drives; a clutch actuator common to both of said clutches; yielding means acting upon said clutch actuator normally to maintain the reverse drive clutch effective; a member moving with said tool-head and acting upon said clutch actuator in opposition to the last named means to cause said clutch actuator to disengage the reverse drive clutch and to engage the forward drive clutch; a latch mechanism, including; a spring-pressed bellcrank lever providing a latch plate adapted to engage a shoulder on the clutch actuator, to hold the clutch actuator in position to maintain the forward drive effective; a trip dog movable with the tool-head during its advance and adapted to engage the bellcrank lever and swing it in opposition to the spring pressure thereon to release said latch mechanism, thereby to permit said yielding means to move the clutch actuator to render effective the reverse drive clutch; and a handle attached to said bell-crank to permit manual release of said latch mechanism to effect emergency reversal of the spindle rotating shaft.

2. A drilling and tapping machine combining a frame provided with a transverse arm; a power shaft journaled in said arm; a tool-head translatably mounted on said frame; a spindle drive shaft extending into said drill-head; a forward and a reverse drive between said power shaft and said spindle drive shaft; a clutch embodied in each of said drives; a clutch actuator common to both clutches; means tending to shift said clutch actuator to cause the reverse drive clutch to be rendered efiective; latch mechanism carried by said transverse arm and acting to prevent movement of said clutch actuator to effect reverse drive; manual means operable at will, to release said latch; a rod rotatably but non-translatably connected with said tool-head: guide means for said rod provided by said arm; means actuated by said rod upon retraction of said head to shift the clutch actuator to render effective the forward drive and to render effective the latch mechanism; a plurality of latch releasing devices carried by said rod, said devices being so arranged as to effect release of said latch at different points in the translation of the tool-head; and manual means to rotate said rod selectively to place said latch releasing devices in operative position.

3. A-drilling and tapping machine combining a frame; a tool-head translatably mounted on said frame; a spindle drive shaft extending into said drill-head; a forward and a reverse drive for said shaft; a clutch embodied in each of said drives; an a tuator for said clutches; means tending to shift said clutch actuator to cause the reverse drive clutch to be rendered effective; latch mechanism acting to prevent movement of said clutch actuator to effect reverse drive; a trip-rod rotatably but non-translatably connected with said tool-head; a trip-dog carried by said rod and adapted, upon retraction of said head, to shift the clutch actuator to render effective the forward drive and to render effective the latch mechanism; a plurality of horizontally and vertically spaced latch releasing devices carried by said rod, said devices being so arranged as to effect release of said latch at different points in the forward translatlon of the tool-head; an oscillatory shaft journaled on said tool-head; a lever for oscillating said oscillatory shaft; an opera tive connection between said oscillatory shaft and said trip-rod to oscillate the latter from the former thereby selectively to place said latch releasing devices in operative position.

ROBERT M. GALLOWVAY. RAYMOND E. STERLING. 

